Biological pathways represent knowledge about molecules, processes and their interactions. Maps of such pathways are used to design and analyze experiments, and for predicting the behavior of biological systems. Pathway information is extremely difficult for biologists to use in its current fragmented and incomplete state, involving a large amount of time and effort to wade through, piece together and analyze. The Pathway Commons research resource is being developed to overcome this roadblock by providing researchers with a convenient single point of access to diverse biological pathway information translated to a common data language. This project is an important step towards the development of a complete and integrated computable map of the cell across all species and developmental stages. Pathway Commons promotes and supports convergence, by the community, to a truly integrated computable and searchable representation of cellular biological processes. Pathway Commons does not compete with or duplicate efforts of pathway databases or software tool providers. Existing database groups provide pathway curation, while Pathway Commons provides mechanism and technology for adding value, disseminating, and reducing duplication of effort. Collaboration with user and database groups is a central component, driven by the desire for maximum synergy and efficiency. The Pathway Commons resource will aggregate datasets from multiple major pathway databases; translate, store, validate, index, integrate, hyperlink and maintain the information for maximum quality access; freely deliver pathway information to the scientific public, both academic and commercial, using advanced internet technology; and, provide open-source end user software for pathway browsing and analysis. User support and training for Pathway Commons and related resources will be freely available to the scientific community.